Charging storage batteries.



No. 780,564. PATENTED JAN. 24, 1905.

J. L. HALL.

CHARGING STORAGE BATTERIES.

'APPLIUATION FILED JULY 13,1903.

Witnesses- Inventor; ly g j y f John L..Ha|l,

fi W4 M Q I At'ty.

No. 780,564. Patented January 24:, 1905.

UNITEDSTATES PATENT OFFICE.

JOHN L. HALL, OF SOHENEOTADY, NE\V YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

CHARGING STORAGE BATTERIES.

SPECIFICATION forming part of Letters Patent No. 780,564, dated January 24, 1905.

Application tiled July 13,1903. Serial No. 165,219.

T all will/011% it y 007106771! ent invention by properly proportioning the Be it known that I, JOHN L. HALL, a citizen windings on the differential coil so that the of the United States, residing at Schenectady, circuit will be opened a safe distance from in the county of Schenectady, State of New the normal line voltage. By using a rheo- 5 York, have invented certain new and useful stat in which the movable switch-arm can be Improvements in Charging Storage Batterlocked at any point the strength ofthe chargies, of which the following is a specification. ing-current can be regulated to suit the capac- This invention relates to apparatus for auity of any battery.

tomatically cutting out a storage battery from The accompanying drawing is a diagram of 10 the charging-circuit when the drop across the circuits including my improved charging debattery terminals reaches a predetermined vice.

value. In devices of this kind it is desirable The generator 1 is connected with the storto be able to set the tripping mechanism so age battery 2 through a main switch 3, pretthat the battery can be cut out at any desired erably of the double-pole type. In the cir- I 5 voltage and when out out will be protected cuit is included a rheostat the contact-steps by a resistance-coil against the ill effects of an of which are shown ate]: and the rotary switchaccidental reclosing of the main switch. arm at 5. The arm is urged to the off po- My invention aims to provide a charging sition by a spring 6, one end of which is atdevice capable of accomplishing these results; tached to the end of the switch-arm and the 20 and it consists in a rheostat similar to that other to a fixed post ofl'set slightly from the shown in my Patent No. 716,222, but with the pivot of the switch-arm and is locked on any 7 0 control-magnet wound with two coils arranged of the steps in the latter part of its movement to oppose each other, one being connected by an arc-shaped catch-bar 7, having notches across the machine-terminals and the other 8, with which engages a spring-pin 9 on the 5 across the battery-terminals or across the rheoarm. The catch-bar is supported on the links statresistances. On starting, the control-mag 10, and a spring 11, having one end attached net flux is due solely to the magnetizing effect to the catch-bar and the other to a fixed post, of the coilconnected across the machine-termi tends to swing it downward, bringing an arnals; but as the voltage of the battery inmature 12, secured to the catch-bar, into co- 3 creases the winding connected across its teroperative relation with a control-magnet 13.

minals exerts an increasing magnetizing e'l'lect On said magnet are two windings 14. 15, either in opposition to that of the other winding, tandem or superposed, one connected by leads and when a point is reached beyond which it 16 17 across the terminals of the generator is not safe to proceed the resultant flux will and the other connected by leads 17 18 across 35 be zero, the armature will be released, and the terminals of the battery. These windings the switch automatically opened. The relaare of course of high resistance and are so tion between the two coils can be proporconnected as to oppose each other. tioned so as to open the circuit at any pre- The operation is as follows: VVhenthe main determined point. This is preferable to a switch is closed, the winding 14 is energized 4 coil responsive to the machine-current only, and attracts the armature 12, pulling down the particularly when charging from a current of catch-bar into operative position. The arm 9 varying voltage, as it is not safe to run the 5 is then turned, first closing the chargingcharging-point of the battery up to anywhere circuit through the resistance-coils of the near the normal voltage of the charging-cirrheostat and then gradually cutting out said 45 cuit, for the reason that if the line voltage coils until the proper point is reached for the should by accident drop below the voltage of best charging effect with the battery in cirthe battery the latter immediately proceeds cuit. The spring-pin 9 entering the correto discharge through the generator and run it spending notch in the catch-bar retains the as a motor. This can be avoided in my presarm in this position. As the voltage of the battery rises the opposing effect of the winding 15 neutralizes that of the winding 1 1 until a predetermined ratio is established, at which point the magnet ceases to attract the armature. The spring 6 thereupon forces up the catch-bar by the lateral pressure of the pin 9 against the inclined side of the notch 8, and the arm 5 being thus released is returned by the spring 6 to the off position. It will be seen that this operation will take place irrespective of any other battery that may be connected with the generator and that if the main switch should be opened while the battery is charging the rheostat will also open automatically, protecting the battery from any evil effects of suddenly closing the main circuit with little or no resistance therein. Moreover, when a battery becomes charged and cuts itself out, the rheostat-arm immediately flies back to the off point, so that ii a person should connect up a second battery to be charged on closing the main switch no trouble would ensue.

In accordance with the patent statutes .l have described the principle of operation of my invention, together with the apparatus which I now consider to represent the best embodiment thereof; but I desire to have it understood that the apparatus shown is only illustrative and that the invention can be carried out by other means.

What 1 claim as new, and desire to secure by Letters Patent of the United States,.is

l. The combination with a generator and a storage battery, of an automatically-opening charging-rheostat provided with a controlmagnet having two windings, one winding being connected across the generator-terminals and the other winding being connected across the battery-terminals and arranged to act always in opposition to the first-mentioned winding.

2. The combination with a generator anda storage battery, of a resistance in series there with, a spring-actuated switch-arm for cutting said resistance in and out, a coil in circuit with the generator for holding said switch closed, and a reverse-current coil connected. with the battery for releasing said arm.

3. The combination with a generator and a storage battery, of a resistance in series therewith, a spring-actuated switch-arm for cutting said resistance in and out, means for locking said arm at any point in its movement, and a reverse-current coil for releasing said arm when the voltage of the battery rises to a predetermined value.

4:. A rheostat provided with a spring-actuated switch-arm, a pivoted catch-bar provided. with notches to arrest said arm at intermediate points of resistance adjustment, an armature carried by said bar, and a magnet cooperating with the armature and having two opposed windings.

In witness whereof I have hereunto set my hand this 10th day of July, 1903.

JOHN L. HALL.

itnesses:

BENJAMIN B. HULL, HELEN ORFORD. 

